Epidemiological Aspects of Hepatitis A: Endemicity Patterns and Molecular Epidemiology

Improvements in hygiene and socio-economic conditions in many parts of the world have led to an epidemiological shift in hepatitis A with a transition from high to low endemicity. Consequently, in these areas, higher proportion of symptomatic disease among adolescents resulting in large-scale community outbreaks has been described. In Tunisia, an increase in the average age at the time of infection has been reported, hence resulting in regular outbreaks, especially household and primary school epidemics. Molecular investigation of such outbreaks, based on the determination of viral genotype and genetic relatedness between hepatitis A virus (HAV) strains, is a useful tool to identify the potential source of HAV contamination but also to assess the virus molecular dynamics over time, such as the introduction of a new genotype or a specific clustering of HAV strains according to the geographical origin. In Sfax city, (Center-East of Tunisia), only HAV strains of genotype IA are circulating. In rural areas, HAV infection is still highly endemic with probably a water-borne transmission pattern. Nevertheless, the considerable genetic heterogeneity observed in urban areas highlights the changing pattern of hepatitis A epidemiology in these settings. Further molecular studies are strongly needed to better understand HAV epidemiology in Tunisia

A year of genomic surveillance reveals how the SARS-CoV-2 pandemic unfolded in Africa.

The progression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in Africa has so far been heterogeneous, and the full impact is not yet well understood. In this study, we describe the genomic epidemiology using a dataset of 8746 genomes from 33 African countries and two overseas territories. We show that the epidemics in most countries were initiated by importations predominantly from Europe, which diminished after the early introduction of international travel restrictions. As the pandemic progressed, ongoing transmission in many countries and increasing mobility led to the emergence and spread within the continent of many variants of concern and interest, such as B.1.351, B.1.525, A.23.1, and C.1.1. Although distorted by low sampling numbers and blind spots, the findings highlight that Africa must not be left behind in the global pandemic response, otherwise it could become a source for new variants

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Comparative study of two coniferous species ( Pinus pinaster Aiton and Cupressus sempervirens L. var. dupreziana [A. Camus] Silba) essential oils: chemical composition and biological activity

Maritime pine ( Pinus pinaster Aiton) and Saharan cypress ( Cupressus sempervirens L. var. dupreziana [A. Camus] Silba) are two cone-bearing seed coniferous woody plants. The chemical composition of their essential oils, isolated from needles and leaves by hydrodistillation, was analyzed with gas chromatography (GC) and gas chromatography mass spectrometry (GC/MS). A total of 66 and 28 compounds were identified, which represented 99.5% and 98.9% of total pine and cypress oils, respectively. Pinus pinaster oil was found to be rich in α-pinene (31.4%), (Z)-caryophyllene (28%), and α-humulene (6.7%); it was characterized by relatively high amounts of monoterpene and sesquiterpene hydrocarbons (44.5% and 46.3%, respectively). The major components identified in cypress oil were manoyl oxide (34.7%), α-pinene (31.8%), α-humulene (9%), and 6-3-carene (8.7%). Results of in vitro antifungal test assays showed that both oils significantly inhibit the growth of 10 plant pathogenic fungi. Herbicidal effects of the oils on seed germination, seed vigor, and seedling growth of three common crop weeds Sinapis arvensis L., Phalaris paradoxa L., and Raphanus raphanistrum L. were also determined; the oils completely inhibited seed germination and seedling growth of all the weeds

Pleural Empyema in Children: Diagnosis and Management in a Pediatric Department in Development Country

Pleural empyema is a serious complication of pneumonia, its morbidity and mortality is important in developing country where hospital resources are limited. Different treatment strategies continue to generate controversy. We reported our experience in diagnosis and management of pleural empyema in children in a pediatric department in a development country.The early adequate surgical treatment in children with pleural empyema results in low morbidity, shorter hospital stay and good long-term outcome